1. Field of the Invention
This invention relates generally to an apparatus for converting electrical signals into physical motion through the use of an electromagnetic transducer. In particular, the present invention provides a robust, low profile motion system having one or more hinged elements which may be easily placed under an object or series of objects in order to impart vibrational motion in response to electrical or motion based signals from a wired or wireless signal source.
2. Description of Related Art
The field of electrodynamic transducers for imparting shaking, push/pull, or other vibrational type motion is well established. In particular, the field of inducing motion in seating systems such that a person seated in the chair experiences vibrational sensations indicative of low frequency (ie. bass) sound includes various types of systems and configurations to accommodate different frequency oscillations. For extremely low frequencies (eg. DC to 20 Hz oscillations) various hydraulic systems, rotary motors with encoders, worm drive systems and sensors for control and position verification (closed-loop) have been used in prior art systems. The applicant for the present invention considered these prior motion systems and found many deficiencies for the applications described in the present invention. Generally, existing seating transducer systems are expensive, complicated to both install and use, and prone to mechanical and other system failures. Generally the complexity and size of these prior art systems require that the mechanical and motion apparatus be integrated in/with the seat in such a way that the seat and motion transducer system must be designed together and produced as one integrated product, and multiple seats in a theater type installation may not share arms or be connected to the adjacent seats, thereby reducing the number of seats that can fit in a room. The backlash in worm drive and hysteresis in the electrical and drive systems also typically limits the operation to around 100 Hz, and since the human body can sense vibration up to approximately 500 Hz, in these systems the range from 100 Hz to 500 Hz cannot be felt by a user.
Current art for creating vibration motion in higher frequencies capable of being sensed by the human body (eg. 20 to 500 Hz) in theater seats typically cannot adequately perform below 20 Hz because they employ inertial shaking systems using a moving mass-spring system to vibrate a portion of the seat. Typically these systems are only capable of vibrating the back or cushion area of a seat, and are not capable of moving the whole seat in unison for a realistic motion sensation.
Thus, a system and device is needed such that it 1) can be used in conjunction with currently installed theater seats as a retrofit upgrade, 2) performs well throughout the range of motion capable of being perceived by the human body (DC to approximately 500 Hz), 3) responds to a combination of frequencies as opposed to singular frequency oscillations, 4) moves the entire seat in one (up and down), two (tilt, up and down), or three (rock, tilt, up and down) axes, with a simple open-loop analog signal power source and low system cost and complexity.